Problem: Expand $(x+2)(3x-6)$.
To expand, we multiply $(3x-6)$ by $x$ and add that product to the product of $(3x-6)$ and $2$. \begin{align*}
(x+2)(3x-6) &= x\cdot(3x-6) +2\cdot(3x-6)\\
&= (3x^2-6x) + (6x-12)
\end{align*}Combining like terms gives a final answer of $\boxed{3x^2-12}$.